5-Hydroxytryptamine innervation of vessels in the rat cerebral cortex

1985 ◽  
Vol 62 (1) ◽  
pp. 42-47 ◽  
Author(s):  
Toru Itakura ◽  
Hideyoshi Yokote ◽  
Hiroshi Kimura ◽  
Ichiro Kamei ◽  
Kazuo Nakakita ◽  
...  
Keyword(s):  
Blood Vessels ◽  
Nerve Fibers ◽  
Ultrastructural Observation ◽  
Intracerebral Injection ◽  
Neuron System ◽  
Content Type ◽  
Carbon Dioxide Reactivity ◽  
Immunohistochemical Techniques ◽  
Immunohistochemical Studies ◽  
Hydrogen Clearance

✓ The role of the central 5-hydroxytryptamine (5-HT) neuron system in cerebral microcirculation of the rat was examined by immunohistochemical and hydrogen clearance methods. Immunohistochemical studies demonstrated 5-HT-immunoreactive nerve fibers along intraparenchymal blood vessels (arterioles, capillaries, and venules). Ultrastructural observation revealed that 5-HT-immunoreactive terminal boutons (0.3 to 1.0 µm in diameter) made contact with the basement membrane of the capillaries. After an intracerebral injection of 5,7-dihydroxytryptamine (5,7-DHT), a neurotoxin to the 5-HT neuron system, no 5-HT-immunoreactive nerve fibers were found around the injection site with immunohistochemical techniques. With the hydrogen clearance method, the 5,7-DHT-injected cortex showed no significant change in regional cerebral blood flow (rCBF) in the presence of normocapnia, but a significant increase in rCBF with hypercapnia, compared with the untreated cortex. These facts strongly suggest that the central 5-HT neuron system has an important role in carbon dioxide reactivity of the cerebral blood vessels.

A role of the central catecholamine neuron in cerebral circulation

1986 ◽  
Vol 65 (3) ◽  
pp. 370-375 ◽  
Author(s):  
Hideyoshi Yokote ◽  
Toru Itakura ◽  
Kunio Nakai ◽  
Ichiro Kamei ◽  
Harumichi Imai ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Blood Vessels ◽  
Cerebral Circulation ◽  
Intracerebral Injection ◽  
Neuron System ◽  
Content Type ◽  
6 Hydroxydopamine ◽  
Catecholamine Neuron

✓ The effect of the central catecholaminergic neurons on the cerebral microcirculation was investigated by means of a unilateral intracerebral injection of 6-hydroxydopamine (6-OHDA) which produced the degeneration of catecholamine (CA) nerve terminals. Subsequent observation with CA histofluorescence revealed an absence of CA fibers in the vicinity of the 6-OHDA injection site. A significant increase in regional cerebral blood flow (rCBF), measured by the hydrogen clearance method, was demonstrated in the CA-depleted cortex under normocapnia as compared with rCBF in the control cortex (CA-depleted cortex 47.0 ± 2.8 ml/100 gm/min; control cortex 38.5 ± 3.5 ml/100 gm/min; p < 0.005). The increased rCBF in the cortex treated with 6-OHDA was suppressed by the iontophoretic replacement of noradrenaline (NA) to the CA-depleted cortex. An iontophoretic replacement of 10−5 M dopamine (DA) mildly suppressed the increased rCBF in the 6-OHDA-treated cortex. The CO2 reactivity in the CA-depleted cortex was significantly lower than that of the control cortex (CA-depleted cortex 2.13% ± 0.67%/mm Hg; control cortex 3.53% ± 0.70%/mm Hg). No change was noticeable in the cerebral glucose metabolism in the CA-depleted cortex in an investigation based on tritiated (3H)-deoxyglucose uptake. It is suggested that the 6-OHDA-induced change in cerebral blood flow (CBF) is not secondary to alterations in cerebral metabolic rate, and that the central NA neuron system innervating intraparenchymal blood vessels regulates CBF through a direct vasoconstrictive effect on the cerebral blood vessels. The central DA neuron system may modulate the cerebral circulation as a mild vasoconstrictor.

Regulation of rCBF by intracortical vasoactive intestinal polypeptide-containing neurons

1987 ◽  
Vol 67 (1) ◽  
pp. 93-96 ◽  
Author(s):  
Toru Itakura ◽  
Hideyoshi Yokote ◽  
Takashi Okuno ◽  
Yutaka Naka ◽  
Kazuo Nakakita ◽  
...  
Keyword(s):  
Blood Flow ◽  
Blood Vessels ◽  
Vasoactive Intestinal Polypeptide ◽  
Content Type ◽  
Intimate Association ◽  
The Mean ◽  
Immunohistochemical Studies ◽  
Hydrogen Clearance ◽  
Intestinal Polypeptide

✓ The role of intracortical vasoactive intestinal polypeptide (VIP)-containing neurons in the regulation of cortical blood flow was investigated in rats by immunohistochemical and hydrogen clearance methods. Immunohistochemical studies revealed an intimate association between intracortical VIP-containing neurons and small blood vessels. Intracortical injection of a VIP solution (10−5 M) produced significantly higher blood flow in the treated cortex (mean ± standard error of the mean: 46.2 ± 4.0 ml/100 gm/min) than in the untreated cortex (36.9 ± 2.4 ml/100 gm/min). These data suggest that intracortical VIP-containing neurons produce dilatation of intracortical blood vessels.

scholarly journals Origin of PACAP-immunoreactive Nerve Fibers Innervating the Subarachnoidal Blood Vessels of the Rat Brain

2004 ◽  
Vol 24 (6) ◽  
pp. 628-635 ◽  
Author(s):  
Florian Martin ◽  
Moesgaard Baeres ◽  
Morten Møller
Keyword(s):  
Blood Vessels ◽  
Trigeminal Ganglion ◽  
Nerve Fibers ◽  
Retrograde Tracing ◽  
Cerebral Vasculature ◽  
Cerebral Blood Vessels ◽  
Subarachnoidal Space ◽  
Amplification System ◽  
Immunohistochemical Studies

The subarachnoidal cerebral blood vessels of the rat are innervated by nerve fibers containing different neuropeptides, e.g. pituitary adenylatecyclase activating polypeptide (PACAP). PACAP dilates brain arterioles and immunohistochemical studies of the rat have indicated that PACAP binds to a VPAC1-receptor in the cerebral vasculature of this species. We have investigated the perikaryal origin of the nerve fibers innervating the subarachnoidal blood vessels of the rat by combined retrograde tracing with Fluorogold and immunohistochemistry. The in vivo neuronal retrograde tracings were done by injection of 2% Fluorogold in water into the subarachnoidal space in the area of the middle cerebral artery. The retrograde transported tracer was detected by use of an antibody against Fluorogold. One week after the injections, the animals were vascularly perfused with Stephanini's fixative and labeled perikarya were found bilaterally in the trigeminal, sphenopalatine, and otic ganglia. The retrograde Fluorogold tracings were combined with immunohistochemistry for PACAP using a mouse monoclonal antibody and the biotinylated tyramide amplification system. Double labeled perikarya containing both Fluoro-gold and PACAP were found predominantly in the trigeminal ganglion, and only rarely in the otic and sphenopalatine ganglion. Summarizing, our retrograde tracings combined with immunohistochemistry indicate that the perikarya in the trigeminal ganglion are the main origin of PACAPergic nerve fibers projecting to the cerebral vasculature of the rat.

Effect of atropine on cerebrovascular responsiveness to carbon dioxide

1978 ◽  
Vol 48 (3) ◽  
pp. 417-422 ◽  
Author(s):  
Masayuki Matsuda ◽  
Shunichi Yoneda ◽  
Hiroshi Gotoh ◽  
Jyoji Handa ◽  
Hajime Handa
Keyword(s):  
Carbon Dioxide ◽  
Blood Vessels ◽  
Nerve Fibers ◽  
Sodium Pentobarbital ◽  
Cerebral Blood Vessels ◽  
Cholinergic Mechanism ◽  
Content Type ◽  
Sagittal Sinus ◽  
The Brain ◽  
Wedge Pressure

✓ Effects of cholinergic inhibition by atropine on cerebral circulation were studied in 15 baboons anesthetized with sodium pentobarbital. Intravertebral infusion of atropine, 0.1 mg/kg, did not cause any changes in cerebral blood flow (CBF), superior sagittal sinus wedge pressure (SSWP), epidural pressure (EDP), cerebral perfusion pressure, or cerebral vascular resistance under normal conditions. Cerebrovascular responsiveness to carbon dioxide (CO2) inhalation was not influenced by atropine. The presence of cholinergic nerve fibers has been proved in the cerebral blood vessels and the existence of cholinergic mechanism suggested in the brain stem, but it is not likely that the cholinergic nerves have tonic control of cerebral blood vessels in the resting state or affect cerebrovascular responsiveness to CO2. The changes in EDP and those in SSWP showed a very good correlation to each other. There was also a good correlation between the changes in CBF and those in EDP or SSWP.

Innervation of endoneurial microvessels in human sural nerve

1992 ◽  
Vol 50 (1) ◽  
pp. 920-921
Author(s):  
John L. Beggs ◽  
Peter C. Johnson ◽  
Astrid G. Olafsen ◽  
C. Jane Watkins
Keyword(s):  
Blood Flow ◽  
Blood Vessels ◽  
Blood Supply ◽  
Peripheral Nerves ◽  
Sural Nerve ◽  
Nerve Fibers ◽  
Arterial Supply ◽  
Autonomic Nerve ◽  
Vasa Nervorum ◽  
Endoneurial Blood Flow

The blood supply (vasa nervorum) to peripheral nerves is composed of an interconnected dual circulation. The endoneurium of nerve fascicles is maintained by the intrinsic circulation which is composed of microvessels primarily of capillary caliber. Transperineurial arterioles link the intrinsic circulation with the extrinsic arterial supply located in the epineurium. Blood flow in the vasa nervorum is neurogenically influenced (1,2). Although a recent hypothesis proposes that endoneurial blood flow is controlled by the action of autonomic nerve fibers associated with epineurial arterioles (2), our recent studies (3) show that in addition to epineurial arterioles other segments of the vasa nervorum are also innervated. In this study, we examine blood vessels of the endoneurium for possible innervation.

Lumbosacral intersegmental epispinal axons and ectopic ventral nerve rootlets

1987 ◽  
Vol 67 (2) ◽  
pp. 269-277 ◽  
Author(s):  
Wesley W. Parke ◽  
Ryo Watanabe
Keyword(s):  
Nerve Root ◽  
Sensory Nerve ◽  
Conus Medullaris ◽  
Spinal Nerve ◽  
Nerve Fibers ◽  
Ventral Horn ◽  
Spinal Nerve Roots ◽  
Nerve Roots ◽  
Content Type ◽  
Almost All

✓ An epispinal system of motor axons virtually covers the ventral and lateral funiculi of the human conus medullaris between the L-2 and S-2 levels. These nerve fibers apparently arise from motor cells of the ventral horn nuclei and join spinal nerve roots caudal to their level of origin. In all observed spinal cords, many of these axons converged at the cord surface and formed an irregular group of ectopic rootlets that could be visually traced to join conventional spinal nerve roots at one to several segments inferior to their original segmental level; occasional rootlets joined a dorsal nerve root. As almost all previous reports of nerve root interconnections involved only the dorsal roots and have been cited to explain a lack of an absolute segmental sensory nerve distribution, it is believed that these intersegmental motor fibers may similarly explain a more diffuse efferent distribution than has previously been suspected.

Immunohistochemical Study of Intralaryngeal Ganglia in the Cat

1992 ◽  
Vol 106 (1) ◽  
pp. 42-46 ◽  
Author(s):  
Kuniyoshi Tsuda ◽  
Takemoto Shin ◽  
Sadahiko Masuko
Keyword(s):  
Neuronal Cell ◽  
Superior Laryngeal Nerve ◽  
Exocrine Secretion ◽  
Nerve Fibers ◽  
Neuronal Cell Bodies ◽  
Calcitonin Gene ◽  
Dense Distribution ◽  
Recurrent Laryngeal Nerves ◽  
Immunohistochemical Techniques ◽  
Almost All

To study the mechanism of autonomic regulation in the larynx, intralaryngeal local ganglia of the cat were investigated using immunohistochemical techniques. Small intralaryngeal ganglia were found in the peripheral portions of internal branches of the superior laryngeal nerve. Ninety-one percent of the ganglionic neurons were immunoreactive (IR) to vasoactive intestinal polypeptide (VIP), and 10% of the VIP-IR cells were also immunoreactive to enkephalin (ENK) and/or substance P (SP). The immunoreactivity of neuronal cell bodies remained unchanged even after denervation of the bilateral superior and recurrent laryngeal nerves. A dense distribution of calcitonin gene-related peptide (CGRP)-IR nerve fibers was found around almost all neuronal cells in the intralaryngeal. ganglia. A few VIP-IR, ENK-IR, and SP-IR nerve fibers were also observed. Only the CGRP-IR fibers disappeared after the denervation experiments. in the laryngeal glands and mucosal arterioles, VIP-IR nerve terminals were found that were also immunoreactive to ENK and/or SP. However, these Immunoreactive nerve endings in the glands and arterioles remained after the denervation experiments. The results of our study indicate that laryngeal exocrine secretion and blood flow are regulated by postganglionic autonomic parasympathetic fibers from intralaryngeal ganglia that contain VIP alone or VIP with ENK and/or SP, and that these ganglionic neurons may be innervated by CGRP-IR extrinsic nerve fibers.

Electron Microscopical and Immunohistochemical Studies on the Induction of "Qi" Employing Needling Manipulation

1992 ◽  
Vol 20 (01) ◽  
pp. 25-35 ◽  
Author(s):  
Michio Kimura ◽  
Kazuo Tohya ◽  
Kyo-ichi Kuroiwa ◽  
Hirohisa Oda ◽  
E. Christo Gorawski ◽  
...  
Keyword(s):  
Mast Cells ◽  
Nerve Fiber ◽  
Functional Relationship ◽  
Nerve Fibers ◽  
Elastic Fibers ◽  
Electron Microscopical Analysis ◽  
Calcitonin Gene ◽  
Transparent Materials ◽  
Electron Microscopical ◽  
Immunohistochemical Studies

During a sparrow-pecking and twisting-needle manipulation to the acupoints BL 23, 24 and 25 for an induction of "Qi", it was found that some transparent materials were binding to the needles after removed from the volunteer's skin. Electron-microscopical analysis of the transparent materials revealed that they corresponded to the injured fascia made up of collagen fibers, elastic fibers, fibroblasts, adipocytes and mast cells. Rarely were nerve fiber-like structures observed in the materials. Immunohistochemically, calcitonin gene-related peptide-positive nerve fibers could be demonstrated in the acupoint BL 24 associated fascia. A possible functional relationship between the needle manipulation and the induction of Qi-sensation is discussed along with the acupoint tissue constitution.

scholarly journals Shedding Light on the Role of the Skin in Vaccine-Induced Protection against the Malaria Sporozoite

mBio ◽  
2018 ◽  
Vol 9 (6) ◽  
Author(s):  
Johanna Patricia Daily
Keyword(s):  
Plasmodium Falciparum ◽  
Blood Vessels ◽  
Blood Stream ◽  
Mosquito Vectors ◽  
Protective Mechanisms ◽  
Partial Protection ◽  
Content Type ◽  
Shed Light ◽  
In Infants And Children

ABSTRACT The most advanced vaccine against Plasmodium falciparum malaria, RTS,S/AS01, provides partial protection in infants and children living in areas of malaria endemicity. Further understanding its mechanisms of protection may allow the development of improved second-generation vaccines. The RTS,S/AS01 vaccine targets the sporozoites injected by mosquito vectors into the dermis which then travel into the blood stream to establish infection in the liver. Flores-Garcia et al. (Y. Flores-Garcia, G. Nasir, C. S. Hopp, C. Munoz, et al., mBio 9:e02194-18, 2018, https://doi.org/10.1128/mBio.02194-18) shed light on early protective responses occurring in the dermis in immunized animals. They demonstrated that immunization impairs sporozoite motility and entry into blood vessels. Furthermore, they established that challenge experiments performed using a dermal route conferred greater protection than intravenous challenge in immunized mice. Thus, the dermal challenge approach captures the additional protective mechanisms occurring in the dermis that reflect the natural physiology of infection. Those studies highlighted the fascinating biology of skin-stage sporozoites and provided additional insights into vaccine-induced protection.

Sign in / Sign up

Export Citation Format

Share Document